A species
Red kangaroo
Osphranter rufus
Fast hopper on springy legs that can pause a pregnancy
You and the red kangaroo last shared an ancestor about 160 million years ago (on 18 December, if life's history were one year).
The red kangaroo is the largest living marsupial, a surprising relative of the koala. It can hop about as fast as a car in town. A stretchy leg cord called a tendon is one of many that store the force of each landing and bounce it forward like a spring. A mother can even pause a pregnancy while she cares for young of different ages.
Males are usually orange-red and females are usually blue-grey, both pale underneath, with a white stripe from mouth to ear. Big males can stand as tall as a grown-up and weigh as much as a grown man. They live in dry inland mainland Australia, feeding in open plains with scattered trees. They graze mostly on grasses and get most of their water from food, so they cope when water is scarce.
A baby called a joey is born as small as a jelly bean and climbs unaided through fur to the pouch. It uses tiny arms to climb and lips to hold on for milk. While one tiny baby suckles inside and an older one nurses outside, the mother can make different milk for each.
Mobs with special names
Red kangaroos gather in social groups called mobs. Adult males are called bucks or boomers and females are called flyers or does.
Said to move forward
They cannot easily hop backwards. They appear on the Australian coat of arms and are said to stand for a nation moving forward.
Surprising swimmers
They can swim quite well for short trips, for example to reach fresh grass or escape danger.